Lamotrigine Use During Pregnancy Not Associated With Birth Defects

Antenatal lamotrigine use does not increase the risk for birth defects and is generally safe for pregnant women who are being treated for epilepsy, according to results of a small study published in the British Journal of Clinical Pharmacology.

In this study, researchers identified a total of 83 women who received lamotrigine during their first trimester. For the purposes of this research, the investigators analyzed short- and long-term data of pediatric patients who were exposed to lamotrigine in utero. Lamotrigine monotherapy was administered in 76 women vs combination therapy (clonazepam [n=4], carbamazepine [n=2], and levetiracetam and phenytoin [n=1]) in the remaining cohort.

As demonstrated by the Finnegan score, the majority of lamotrigine-exposed infants (87.6%) had no withdrawal symptoms. In addition, none of the infants who were exposed to lamotrigine in utero demonstrated significant withdrawal.

The researchers found no major or significant malformations in the newborns exposed to the medication. In addition, no significant neurodevelopmental disorders were found. Compared with controls, infants who were exposed to lamotrigine had lower rates of speech delay at 12 years (18.0% vs 7.2%, respectively; P =.036).

Because all the infants included in this analysis were born in Israel at a single tertiary center, the findings of this study may not be applicable to the larger population. Also, because of the longitudinal and retrospective nature of this study, as well as the single follow-up survey used to assess long-term outcomes, the results are not strong enough to demonstrate definite safety of lamotrigine during pregnancy.

Despite these limitations, this study adds to current data suggesting "that in utero exposure to lamotrigine does not increase the risk of birth malformations and neonatal complications."